Since Apple stripped the iPhone weather app from the iPad, it left the door open for 3rd parties to do their thing. They've done just that, and I'd like to spotlight two apps that come at weather from very different places.
We've looked briefly at both these apps. Our Victor Agreda Jr. used and liked WeatherBug Elite, and Erica Sadun took a quick look at Weather HD in April.
Let's start with WeatherBug Elite for iPad and look more closely. The app is free, and has a compelling display on the iPad screen. It is the more conventional app of the two, with radar and cloud cover overlays, animation, severe weather alerts from the National Weather Service, Extended 7 day and hourly forecasts, and webcams for most locations that show you a semi-live view of the current weather. You can save multiple locations, and get to them with a tap. As I do a lot of landscape photography, I really appreciate the infrared and visible satellite maps, that show you cloud cover down to the street level. The app works in portrait or landscape mode, and it can cache weather data for off-line viewing. I think this app is for serious weather consumers, and I have found it reliable and up to date. There are also versions for Windows and Macs, and an iPhone version. Strangely, the iPhone version sells for $0.99, while the iPad version is free. You can also get a free version for the iPhone, but it has ads.